Prevalence of gene and SNV changes. Distribution of prevalence of gene (A,C,E) and SNV changes (B,D,F) occurring in infant–infant, mother–infant, and HMP adult–adult QP pairs. Here, prevalence is defined as the fraction of HMP adults that harbor a SNV or gene. Additional cohorts are used to compute prevalence in Supplemental Figures S12 through S14. The null distributions in gray show the expectation for random de novo events (Methods). By definition, gene gains cannot occur de novo. In B, D, and F, the prevalence bin < 0 indicates that no HMP adult harbors the sweeping allele other than the person in which the allele arises, and the prevalence bin > 1 indicates that the allele is present in all HMP adults.
